<?xml version="1.0" encoding="UTF-8"?>
<!-- Copyright 2007 XBRL International. All Rights Reserved.   
 
This version is non-normative - it should be identical to the normative version that is contained in Appendix A of the relevant specification except for this comment.

Following the schema maintenance policy of XBRL International, it is the intent (but is not guaranteed) that the location of non-normative versions of these schemas on the web will be as follows:

1)	While any schema is the most current RECOMMENDED version and until it is superseded by any additional errata corrections a non-normative version will reside on the web in the directory http://www.xbrl.org/2008/ - during the drafting process for this specification this directory should contain a copy of the most recent published version of the schema at http://www.xbrl.org/2008/boolean-filter.xsd.

2)	A non-normative version of each schema as corrected by any update to the RECOMMENDATION will be archived in perpetuity on the web in a directory that will contain a unique identification indicating the date of the update.

-->
<schema 
  targetNamespace="http://xbrl.org/2008/filter/boolean"
  elementFormDefault="qualified"
  xmlns="http://www.w3.org/2001/XMLSchema" 
  xmlns:bf="http://xbrl.org/2008/filter/boolean" 
  xmlns:variable="http://xbrl.org/2008/variable"
  xmlns:link="http://www.xbrl.org/2003/linkbase" 
>

  <import namespace="http://www.xbrl.org/2003/XLink" 
    schemaLocation="http://www.xbrl.org/2003/xl-2003-12-31.xsd"/>

  <import namespace="http://xbrl.org/2008/variable" 
    schemaLocation="variable.xsd"/>

  <annotation>
    <appinfo>

      <link:arcroleType id="boolean-filter"
            cyclesAllowed="undirected" 
            arcroleURI="http://xbrl.org/arcrole/2008/boolean-filter">
        <link:definition>boolean-filter has sub-filter</link:definition>
        <link:usedOn>variable:variableFilterArc</link:usedOn>
      </link:arcroleType>

    </appinfo>
  </annotation>

  <element id="xml-and-filter"
  name="andFilter" 
  substitutionGroup="variable:filter"
  type="variable:resource.type"/>

  <element id="xml-or-filter"
  name="orFilter" 
  substitutionGroup="variable:filter"
  type="variable:resource.type"/>

</schema>